Forces and motion

1. The push or pull on an object with mass causes it to change its velocity
4. friction opposes the movement between two contact surfaces that slide against each other.
5. the quantity of motion of a moving body, measured as a product of its mass and velocity.
6. third Law of Motion for every action (force) in nature there is an equal and opposite reaction.
8. the moving of something from its place or position.
14. a vehicle's capacity to gain speed within a short time.
15. a force which tries to pull two objects toward each other.
16. the resistance that one surface or object encounters when moving over another.
17. Method a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.
19. the speed in combination with the direction of motion of an object.
20. the act or quality of acting or moving fast; rapidity.

2. a scientific procedure undertaken to make a discovery, test a hypothesis, or demonstrate a known fact.
3. force When two forces are the same strength but act in opposite direction
7. a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force.
9. friction a force that keeps an object at rest
10. force the force acting on an object in curvilinear motion directed towards the axis of rotation or center of curvature.
11. resistance a kind of friction (a force that opposes motion) which occurs between air and another object.
12. a body's relative mass or the quantity of matter contained by it, giving rise to a downward force; the heaviness of a person or thing.
13. second Law of Motion the acceleration of an object is directly related to the net force and inversely related to its mass.
18. Theory a well-substantiated explanation of some aspect of the natural world, based on a body of facts